ok, further to the (sound beginning being clipped) I have found that stereo waves are not correctly supported. in that Panning has no effect on them.
Whilst strictly not a bug, it is also a failure. Stereo samples should be able to be panned then same as mono samples.
I found this
http://stackoverflow.com/questions/9118957/setting-panning-in-openal-ios
Which explains that OpenAl wont pan any sounds with more than 1 channel. And that for this to operate correctly a stereo sample should be operated as two separate channels that then allow panning.
It does seem that the sound implementation Mark has used, is (in some ways) severely flawed, or botched?